Modulation of an immune or inflammatory response may be valuable in various therapeutic settings. Downmodulation of an immune or inflammatory response may be desirable in treatments various kinds of autoimmune or inflammatory diseases. Upmodulation of any immune response may be valuable to, for example, amplify a response to a particular antigen, for example, an antigen contained in a vaccine or an antigen preferentially expressed on a cancer cell or a cell mediating a fibrotic disease. Thus, molecules capable of modulating an immune or inflammatory response are potentially of therapeutic value in a variety of therapeutic settings. The present invention provides therapeutic agents to diagnose and treat diseases characterized by inappropriate and/or abnormal inflammation and/or immune responses. Some of these agents can stimulate an immune response. Others can inhibit inflammation and/or immune responses.